Trimming mechanism



G. STEVENSON 2;, H 65,3 1 3 TRIMMING MECHANISM Original Filed May 14,1937' '7 Sheets-Sheet l a 5 Gegffrey Sfevenson July 11,, H939;

, G. STEVENSON TRIMMING MECHANISM Original Filed May 14, 1937 7Sheets-Sheet 3 7 Sheets-Sheet 4 m M% QQJ W m W Q W w W. m min m Q n 0w.NNMI? k v J A J m x\ M m J x 3% .Q

' July 11, 1939. G. STEVENSON TRIMMING MECHANISM Original Filed May 14,1937 July 11, 1939. STEVENSON 2, 1 65,313

TRIMMING MECHANISM Original F iled May 14, 1937 7 sheets-she t 5 I Fig.,7. 5 2i 2 Fig. 6.

6e%e3 Sfeuensan July 11, 1939. ca. STEVENSON TRIMMING MECHANISM 7sheets-sheet 6 Original Filed May 14. 193:? Fig. 8.

July 11, 1939. STEVENSON 2,165,313

TRIMMING MECHANISM Original Filed May 14, 1937 7 Sheets-Sheet 7 PatentedJuly 11, 1939 Geofl'rey Stevenson, Brookline, Mass.

Original application May 14, 1937, Serial No.

142,696. Divided and this application October 25, 1937, Serial No.170,913

.58 Claims.

This invention relates to new and useful improvements in trimmingmechanisms generally,

although more particularly to a trimming mechanism adapted for use insewing machines for 5 trimming or pinking an edge or the edges ofsuperposed fabrics prior to the seaming operation.

This application constitutes a division of my parent application SerialNo. 142,696, filed May 10 14, 1937 for improvements in Combined seamingand pinking machines.

The principal object of the invention is to provide an edge trimmingmechanism which is normally positioned for cooperation with the stitch-15 ing mechanism to trim the work above the base or work plate and intimed relation to the needle reciprocations, and which is depressible soas to leave the upper face of the base unobstructed for the free passageof work during plain seaming operations.

With the above and other objects in view which will more fully appear,the nature of the invention will be more clearly understood by followingthe description, the appended claims, and the 25 several viewsillustrated in the accompanying drawings.

In the drawings:

Figure 1 is a front elevation of a sewing machine embodying myinvention, the pinking unit 30 being depressed below the bedplate,

Figure 2 is a bottom plan view thereof,

Figure 3 is an enlarged vertical longitudinal sectional view through thebed plate showing the pinking unit in its depressed position, I

5 Figure .4 is a similar view but showing the pinking unit in itselevated or working position,

Figure 5 is a vertical longitudinal section taken through the bed plateand the pinking unit,

Figure 6 is a vertical cross section taken on the line 6-6 of Figure 4,

Figure 7 is a vertical cross section taken on the line 'Il of Figure 4,

Figure 8 is a detail vertical cross section showing the stops forlimiting the upper and lower positions of the pinking unit,

' Figure 9 is a detail plan view showing the pinking unit in itselevated position, together with a plate which. covers the' openingimmediately 5 in front of the unit, a

' Figure 10 is a perspective view of the filler plate shown in Figure 9.

Figure 11 is a plan view of the trimmer unit showing a separatingplateand ahemmer at- 55 tached,

' ant front and rear depressed seats 9, 9

(01. lei-11.5)

Figure 12 is a central vertical longitudinal sec- I tion thereof,

Figure 13 is a perspective view of the pinking unit,

Figure 14 is a perspective viewshowing the 5 supporting lever and theledger blade holder in separated relation,

Figure 15 is a perspective view of the upper cutting element, and

Figure 16 isa perspective view of the knife 10 lever and the knifemounted thereon.

Like reference numerals designate corresponding parts throughout theseveral figures of the drawings. v

Referring to the drawings, my invention is pref 15 erably applied to asewing machine which embodies a main frame A having a base orbed plate5, a standard 6, a horizontal arm I which projects from the upper end of'the standard and extends longitudinally over the base, and a stitch 20ing head 8 which is mounted on the free end of the arm 1, said basebeing provided with a longitudinal opening 9 under said head. The base 5is provided at its ends with integral and depending bearing arms 5 5 andwith integral and depending. front and rear longitudinally extendingwalls 5, 5*, as well as an integral and depending bearing arm 5 which isspaced from the bearing arm 5". The upper surface of the base 5is milledalong the sides of the opening 9 to form result- A main shaft l0 extendslongitudinally of and is journaled in the arm 1. A verticallyreciprocatory needle bar ll carrying a needle I2, .is mounted in thehead 8 and is driven from the main shaft 85 by the usual connectionswhich reciprocate the needle once for every rotation of the main shaft.A throat plate l3 which is supported by the seats 9, 9 of the base andextends centrally across the opening 9, is provided with a needleopening l4 adjacent the right hand edge thereof and with feed slots l5'(see Fig. 9). The portions of the opening 9 on opposite sides ofthethroat plate v are adapted to be closed by removable cover plates l6and I1 respectively which are slidably mounted on the seats 9 9*. Apresser bar l8 is mounted in the head 8 and fixed to the lower endthereof ,is a presser foot l9 which is positioned directly above thethroat plate [3 and is provided with a needle opening 20. Anintermittent 4-motion feed dog 2| is positioned in the feed slots ill ofthe throat plate for cooperation with the presser foot to feed the workrearwardly and is operated from the main shaft in the usual manner.Cooperating with the needle to form stitches is a rotary loop taker orhook 22 which is'located below the cover plate I 6 and on the left handside of the needle. This hook is mounted on a vertical shaft 23 which isjourcouplings 28 and 29, the shaft 21 being located below the needle andin spaced relation to the base. It will be noted that the shaft 21extends longitudinally of the base and is disposed in the vertical planecontaining the needle.

. A trimming mechanism is disposed on the right hand side of the needle,i. e., on the side of the needle opposite the rotary loop taker. Thistrimming mechanism includes an upper cutting element or ledger blade Band a cooperating lower cutting element or knife C. The upper element Bis separate from the presser foot I9, and when said element B is in itsefiective or cutting position, it is disposed above the plane of thebase 5. Both cutting elements B and C are mounted on a support D whichis located below the base, the

elements and the support being adjustable longitudinally of the base asa unit by slots 52 whereby the distance between the line of seam of thefabrics and the trimmed edge thereof may be varied. Furthermose, bothelements are mov-- able upwardly as a unit through the opening 9 of thebase to an effective or operating position, or downwardly as a unitthrough said openings to an ineffective or inoperative position belowthe base 5. I

The support D is in the form of a lever having spaced longitudinal arms39, 30 which extend from its right hand end and are fulcrumed as at 3|,3| on lugs 32, 32.projecting downwardly from the base, the lever thusbeing fulcrumed on a horizontal axis which is parallel to the line offeed and is located below the base opening 9 and the standard 5. Rigidlyconnected to and depending from the free end of the supporting lever Dare spaced hanger arms 33, 33 and the under face of the supporting leveris provided with a central longitudinal groove 34.

A coil spring d is interposed between the base the lever downwardly, theupper and lower ends of the spring being positioned in seatsrespectively formed in the under face of the base and in the upper faceof the lever.

A manually operable means for elevating the support D includes a bracket38 which is attached to the under face of the base 5 in" front of andintermediate the ends of the support. A horizontal cam shaft 39 isjournaled in the bracket and fixed to said shaft is a cam 40 whichengages the under face of the supporting'lever D directly in front ofthe groove 34 therein. The cam shaft 39 is provided with a dependingcrank arm 4|. A vertically disposed lever 42 isfulcrumed intermediateits ends 'as at 43 to the front wall 5". of the base 5. The lower arm ofthis lever is connected by a link 44 to the crank arm 4|, and the upperarm of said lever projects through a longitudinally extending opening 45formed in thebase 5. A bracket 45 is mounted on the upper face of thebase 5 and includes a post 41 which is disposed on the right hand sideof the pper arm of said lever. A manually operable eccentric 48 isfulcrumed "as at 49 on said post for engaging the upper arm of the leverand effecting the rocking movement of the cam to raise the support Dagainst the tension of the spring (1. A stop 59 is attached to thebracket 38 and functions to limit the downward move- 'ment of thesupport D when the cam 40 is moved in the opposite direction. A stopscrew 5| is threadably engaged in the support D for coop eration withthe under face of the base 5 to variably limit the upward movement ofsaid support.

Mounted in the groove 34 of the supporting lever D for adjustmentstowards and from the needle I2, is a holder E for the upper cuttingelement B, the holder being provided with longitudinal slots 52, 52through which clamping screws 53 pass into the lever D. The holder E isthus normally clamped to and supported by the lever D and isconsequently movable. up and down therewith, but can be adjustedlongitudinally of the base when so desired? The right hand end of theholder is provided with spaced and upwardly projecting arms 54, 54 whichproject between the arms 39, 39 of the supporting lever D and support ahorizontal pivot pin 55. Rigidly connected to the left hand end of theholder and disposed in registry with the base opening 9 at the right ofthe throat plate is a neck 56 which terminates at its upper end inspaced horizontal arms 51, 51 which project towards the needle, and theupper cutting element or ledger blade B is rigidly mounted on said armsby screws The upper cutting element or ledger blade B is provided with aV-shaped opening 59 forming resultant cutting edges 60, 60 whichconverge toward the needle l2 and merge at the apex-6| at an angle ofless than 90; and with depending'guide lugs 62, 62 to prevent the escapeof the lower cutting element or knife 0 from registering relation withthe ledger blade in the most open working position of the knife, as wellas to serve as a gage for the material. The blade B is also providedwith spaced attaching arms 53, 63 which rest upon the spaced supportingarms 51, 51 and are secured thereto by the screws 58.

A lever F which supports the lower cutting elementor knife C is mountedfor vertical reciprocations on the support D through the medium of theholder E. This knife lever F is located under the holder E and isprovided at the end opposite the knife C with an upwardly projectingrigid arm 64 which is fulcrumedon the horizontal piv- 01', pin of theledger blade holder E. A knife arm 65 is pivoted at its lower endtoswing about a horizontal pivot 56 mounted in the free end of the leverF, and the upper' end of the arm projects upwardly towards the openingof the ledger blade B. The knife C is mounted on the arm 65 for verticaladjustments by means of a clamping screw 61 carried by the knife and aslot 68 formed in the arm. The knife C is V-shaped in cross sectionforming converging cutting edges 69, 69 which enter into and cooperatewith the cutting edges 59, of the ledger blade to perform the pinkingoperation. The knife C is preedges have point contact which advancestoward the apex as the cutting progresses by the entry When the uppercutting element or ledger blade of the knife C into the ledger blade B,the cutting terminating when the two apices coincide. The knife C yieldsabout the pivot 69 during the cutting operation, the edges 69, 69crossing the cooperating edges of the ledger blade but the angle ofthe'faces of the knife C being less in the plane of the ledger bladethan that of the ledger blade opening whereby the knife C may enter intothe ledger blade. This angular relation between the cutting edges of theledger blade and the cutting edges of the knife is disclosed and claimedin the patent to Gruman 1,891,308, December 20, 1932. The cutting edgesof the knife are maintained in yieldable engagement with the cuttingedges of the ledger blade during cutting movements of the knife, bymeans of a coil spring '10 which is adjustably anchored at one end tothe arm 64 of the knife lever F by an adjustable screw H and nut 12, andby a link 13 which is connected at one end to the other end of thespring, and at'its. other end to the lower end of the knife arm 65 belowthe pivot 66 thereof by a screw 14. A manually operable cam ber ofstitches to each pink cut by the knife C, or for silencing the knife. Abearing bracket 19,

is attached to the under face of the horizontal frame arm I, andjournaled in this bracket is a longitudinally extending counter ordriven shaft 11 which parallels the main shaft l0, the left hand end ofthe shaft projecting beyond the bracket 16. A ball eccentric 18 is fixedto a stop collar which is secured to the right hand end of 'the countershaft H. A transversely disposed rockshaft I9 is journaled in thedepending bearing arm 5, of the base, and the rear end thereof isprovided with a horizontally extending rock arm 80 which is pivotallyconnected as at to the lower end of a verticallink, or pitman 82 whichextends upwardly through an opening 83- in the base and has its upperend connected to the ball eccentric 19 on the counter shaft. Fixed tothe front end of the rock shaft 19 is a depending rock arm 84 having asegmental slot extending longitudinally thereof. A horizontal rock shaft86 is journaled in the lower ends of the depending arms 33,33 of thesupporting lever D, and a rocking frame 81 is journaled on said shaftintermediate said arms. The rocking frame 81 comprises a hub 88 whichsurrounds the shaft and .is rigidly connected thereto by a transversepin 89, together with spaced rock arms '90, 90 which are integral withthe hub and project upwardly at aninclination towards the free end ofthe knife supporting lever F, the arms being pivotally connected to saidfree end of the lever D by links 9|, 9|. Fixed to the front end of therock shaft 86 is an upstanding rock arm 92 which is pivotally connectedto one end of a link 93, the other end of the link having an adjustableconnection 94 with the rock arm 84 and the segmental slot 85 therein,whereby the vertical stroke of the knife C may be varied.

The counter shaft TI is rotated from the main shaft I0 through themedium of a selective gear coupling which is indicated generally at 95and fully described in my parent application.

Bis in its elevated or operative position as shown in Fig. 4, it is in ahorizontal plane spaced above the upper surface of the base 5 forpermitting under and pinked. -In order to'support this edge portion orportions against sagging into the opening 9 of the base 5 immediately infront of the lower cutting element C, I have provided an L- shapedfiller plate 96 (Figs. 9 and which is attached, subsequently to thecutting elements being elevated, to the front seat 9 of the base 5 by ascrew 91. This plate 96 comprises-an attaching arm 98 and a rearwardlyprojecting arm 99 having a beveled rear end I00 which parallels but isspaced from the adjacent cutting edge 69 of the knife C.

In certain operations, I employ a folder [M which is attached to aseparating plate I02, the latter being mounted on the arms 51 of theholder E. The separating plate serves to maintain the edge portion ofthe upper fabric separated from the movable knife C, and alsoconstitutes a solid backing for the ledger'bladeB to maintain the latteragainst being moved upwardly .by the thrust of the knife C. It will beobvious that the separating plate equipment has utility in a pinkingmechanism per se, and independently of any stitch forming mechanism,since it is possible to form a seam such as is shown in Figure 12 ofthedrawings on a sewing machine and then put it through the pinkingmechanism per se claimed herein.

'It is of course to be understood that the details of structure andarrangement of parts may be variously changed and modifiedwithoutdeparting from the spirit andscope of my invention. 7 Y

I claim:

1. A pinking mechanism for sewing machines having a horizontal base,comprising a stationary horizontally disposed ledger blade having acutting opening therein, and a cooperating vertically reciprocatoryknife supported below the base and operable in said opening.

2. A pinking mechanism forsewing machines having a horizontal base,comprising a stationary horizontally disposed ledger blade having acutting opening therein, a lever fulcrumed on the base and having oneend positioned for vertical reciprocations below the base and operablein said opening, and a knife mounted on said end of the lever forcooperation with the opening in the ledger blade.

3. A pinking mechanism for sewing machines having a base, comprising aledger blade disposed in the general plane of the base and having aV-shaped opening therein, a cooperating vertically reciprocatoryveshaped knifesupported below the base and operable in said opening, andmeans for maintaining the V of the blade opening and the V of the knifein yieldable engagemen't during cutting movements of the knife.

4. A pinking mechanism for sewing machines having a base, comprising aledger blade disposed in the general plane of the base and having aV-shaped opening therein, a cooperating ver-- tically reciprocatoryV--shaped knife supported below the base and operable in said opening,and means engaging the knife for maintaining the V of the knife inyieldable engagement with having a base, comprising a ledger blade sabove the base, a lever pivoted below the base for oscillations about ahorizontal axis, a knife pivotally mounted on the lever for cooperationwith the ledger .blade, and means cooperating with the knife and leverfor maintaining the knife in yieldable engagement with the ledger bladeduring cutting movements of the knife.

6. A pinking mechanism for sewing machines having a base, comprising astationary ledger blade disposed in the general plane of the base andhaving a V-shaped opening therein, a lever pivoted below the base foroscillations about a horizontal axis, a v-shaped knife mounted on saidlever for cooperation with the opening in the ledger blade, and meansfor reciprocating said knife including a bell crank lever mounted belowthe lever and having one end pivotally connected to said lever.

'7. A pinking mechanism for sewing machines having a base, comprising aledger blade having a V-shaped opening therein and disposed in a planeparallel with and spaced above the base, a supporting element for theledger blade mounted below and projecting upwardly through the base, anda cooperating V-shaped cutting element supported below the base andoperable in'said openmg.

8. A pinking mechanism for sewing machines having a base, comprising astationary ledger blade having a V-shaped opening therein anddisposed ina plane parallel with and spaced above the base, and a verticallyreciprocatory V-shaped knife supported below the base and provided witha cutting edge on its upper end for cooperation with the opening in theledger blade during the upstroke of the knife.

9. A pinking mechanism for sewing machines having a base, comprisingcooperating cutting elements, one said element being disposedhorizontally and having a cutting opening therein and the other saidelement being supported below the base and operable in said opening, andmeans for effecting a depression of said cutting elements to anineffective cutting position below the base.

10. A pinking mechanism for sewing machines having a base, comprisingupper and lower cooperating cutting elements, the upper element beingdisposed above the base and the lower element being supported below thebase, and means for effecting a depression of said cutting elementsbelow the upper face of the base to an ineffective cutting position.

11. A trimming mechanism for sewing machines having a base, comprisingupper and lower cooperating cutting elements, the upper element beingdisposed above the base and the lower element being supported below thebase, and means including a manually operable lever for effecting adepression of said cutting elements as a unit to an inefiective cuttingposition below the base.

12. A trimming mechanism for sewing machines having a base, comprisingupper and lower cooperating cutting elements, the upper element beingdisposed above the base and the lower element being supported below thebase, and means for effecting a depression of said cutting elements as aunit below the upper face of the base to an ineffective cuttingposition.

13. A trimming mechanism for sewing machines having a base, comprising avertically reciprocatory support mounted below the base and having aportion projecting upwardly therethrough, a ledger blade mounted on theprojecting portion of the support and spaced above the base, acooperating vertically reciprocatory knife mounted below the base, andmeans for eifecting a-depression of said ledger blade and knife to anineffective cutting position below the base.

14. A trimming mechanism for sewing machines having a base, comprisingupper and lower cooperating cutting elements, the upper element beingdisposed above the base and the lower element being supported below thebase, and manually operable means for normally retaining the cuttingelements in effective cutting position and for effecting a depression ofsaid elements to an ineffective cutting position below the base uponrelease of said retaining means.

15. A trimming mechanism for sewing machines having a base, comprisingupper and lower cooperating cutting elements, the upper element beingdisposed above the base and the lower element being supported below thebase, and manually operable means including a cam for normally retainingthe cutting elements in eiTective cutting position and for effecting adepression of said elements to an ineffective cutting position below thebase upon release of said retaining means.

16. A trimming mechanism for sewing machines having a base, comprisingupper and lower cooperatingcutting elements, the upper element beingdisposed above the base and the lower element being supported below thebase, and manually" operable means including a cam for normallyretaining the cutting elements in effective cutting position, and aspring for depressing said elements to an ineffective cutting positionbelow the base upon release of said retaining means.

17. A trimming mechanism for sewing machines comprising a base having anopening, a support mounted below the base to oscillate about ahorizontal axis, a ledger blade spaced above the opening and mounted onthe support, manually operable means for normally retaining the supportagainst swinging movement, a knife mounted below the base to swing abouta horizontal axis, a knife mounted on said lever and projecting upwardlythrough said opening for cooperation with said ledger blade, and meansfor oscillating said knife lever, said support upon release of saidretaining means moving to a position wherein said ledger blade and saidknife will be in an ineffective cutting position below the base.

18. A trimming mechanism for sewing machines comprising a base having anopening, a support mounted below the base to oscillate about ahorizontal axis, a holder mounted on said support and having an endprojecting upwardly through said opening, a ledger blade spaced abovethe opening and mounted-on the projecting end of the support, manuallyoperable means for ,normally retaining the support and holder 19. Atrimming mechanismjor sewing me.- 7

the opening and mounted on the support, means for retaining the supportagainst swinging movement, a knife lever mounted on the support belowthe base to swing about a horizontal axis, a knife mounted on said leverand projecting upwardly through said opening for cooperation with saidledger blade, and means for oscillating said knife lever.

20. A trimming mechanism for sewing machines comprising a base having an.opening, a support mounted below the base to oscillate about ahorizontal axis, a holder mounted on said support and having an endprojecting upwardly through said opening, a ledger blade spaced abovethe opening and mounted on the projecting end of the support, means for'retaining the support against swinging movement, a knife lever locatedbelow the holder and 'fulcrumed thereon to swing about a horizontalaxis, a knife mounted on said lever and projecting upwardly through saidopening for cooperation with said ledger blade, and means foroscillating said knife lever including a bell crank lever anda linkinterposed between the holder and the lever. 21. A pinking mechanism forsewing machines having a base, comprising a-ledger blade spaced abovethe base and provided with an opening forming converging cutting edges,and a verti- I,

'cally reciprocatory knife supported below the base and havingconverging cutting edges for cooperation with the cutting edges of theledger blade.

22. A pinking mechanism for sewing machines having a base, comprising aledger blade spaced above the base and provided with an opening formingconverging cutting edges, and a verticaly reciprocatory'knife supportedbelow the base and having converging cutting edges for cooperation withthe cutting edges of the ledger blade, the,

each other during cutting movements of the a knife.

24. A pinking mechanism for sewing machines having a base, comprising, astationary ledger blade spaced above the base and provided with anopening forming converging cutting edges, a vertically reciprocatoryknife supported below the base and having converging cutting edges forcooperation with the cutting edges of the ledger blade, andmeans'coope'rating with the knife for maintaining the cutting edges ofthe blade and knife in yieldable engagement with each other.

during cutting movements of the knife.

25. A pinking mechanism for sewing machines having a base, comprising astationary ledger blade spaced above the base and provided with anopening forming converging cutting edges, a. vertically reciprocatoryknife supported below the base and having converging cutting edges for.

cooperation with the cutting edges of the ledger blade being more thanthe angle of the cutting edges of the knife, and means for maintainingthe cutting edges of the blade and knife in yieldable engagement witheaoh other during cutting movements of the knife.

26. A pinking mechanism for sewing machines having a base, comprising-astationary ledger blade spaced above the base and provided with anopening forihing converging cutting edges, a vertically reciprocatoryknife supported below the base and having converging cutting edges forcooperation with the cutting edges of the ledger blade, the angle of thecutting edges of the ledger blade being more than the angle of thecutting edges of the knife, and means cooperating with the knife formaintaining'the cutting edges of the blade and knife in yieldableengagement with each other during cutting movements of the knife.

27. A pinking mechanism for sewing machines having a base, comprising aledger blade spaced above the base and provided with an opening formingconverging cutting edges, a lever pivoted below the base foroscillations about a horizontal axis, and a knife mounted on said leverand having converging cutting edges for cooperation with the cuttingedges of the ledger blade. 28. A pinking mechanism for sewing machineshaving a base comprising a ledger blade spaced above the base andprovided with an opening forming converging cutting edges, a leverpivoted below the base for oscillations about a horizontal axis, a knifemounted on said lever and having converging cutting edges forcooperation with the cutting edges of the ledger blade, and meansincludinglever and link connections for reciprocating said knife. V

29.1%. pinking mechanism for sewing machines having a base, comprisingastationaryledgerblade spaced above the base and provided with anopening forming converging cutting edges, and a vertically reciprocatoryknife supported below the base and provided with converging cuttingedges on its upper end for cooperation with the cutting edges oftheledger blade during the upstroke of the knife.

30. A pinking mechanism for sewing machines having a base, comprising aledger blade spaced above the base and provided with an opening formingconverging cutting edges, and a vertically reciprocatory knifesupportedbelow the base and having converging cutting edges forcooperation with the cutting edges of the ledger blade, and means fordepressing said ledger blade and said knife to an ineffective cuttingposition.

31. A pinking mechanism for sewing machines having a base, comprising aledger blade spaced above the base and provided with an opening formingconverging cutting edges, and a vertically reciprocatory knife supportedbelow the base and having converging cutting edges for cooperation withthe cuttingedges of the" ledger blade,

manually-operable means for normally retaining the ledger blade and theknife in effective cutting position, and means for depressing said bladeand knife to an ineffective cutting position upon release of saidretaining -means.

32. A pinking mechanism for sewing machinescomprising a base having anopening, a support mounted below the base to oscillate about ahorizontal axis, a ledger blade spaced above the opening and mounted onthe support, said ledger blade being provided with an opening formingconverging cutting edges, means for retaining the support againstswinging movement, a knife lever 15 1 blade, the angle of the cuttingedges of the ledger, mounted on the support below, the base toswingopening and mounted on the projecting end of the support, said ledgerblade having an opening forming converging cutting edges, means forretaining the support against swinging movement,

a knife lever located below the holder and fulcrumed thereon to swingabout a horizontal axis, a knife mounted on said lever and projectingupwardly through said opening for cooperation with the cutting edges ofsaid ledger blade, and means for oscillating said knife lever.

34. A pinking mechanism for sewing machines comprising a base having anopening,,a support mounted below the base to oscillate about ahorizontal axis, a ledger blade spaced above the opening and mounted onthe support, saidledger blade being provided with an .opening formingconverging cutting edges, means for retaining the support againstswinging movement, a knife lever mounted on the support below the baseto swing about a horizontal axis, a knife mounted on said lever andprojecting upwardly through said opening for cooperation with thecutting edges of said ledger blade, and means for oscillating said knifelever, and means for efiecting a depression of the ledger blade and theknife lever upon release of said retaining means to an inefiectivecutting position belowthe base.

35. A pinking mechanism for sewing machines having a-base, comprising aledger blade spaced above the base and provided with an opening formingconverging cutting edges, a vertically reciprocatory knife supportedbelow the base and having converging cutting edges for cooperation withthe cutting edges of the ledger blade, and a separating and ledger bladebacking-plate positioned above the ledger blade.

36. A pinking mechanism for sewing machines having a base, comprising aledger blade spaced above the base and provided with an opening formingconverging cutting edges, a vertically reciprocatory knife supportedbelow the base and having converging cutting edges for cooperation withthe cutting edges of the ledger blade, and a separating and ledger bladebasking plate positioned above the ledger plate and prbvided with a;opening for receiving the upper end of the 3'7. A pinking mechanism forsewing machines having a base, comprising a ledger blade spaced abovethe base and provided with an opening forming converging cutting edges,a vertically reciprocatory knife supported below the base and havingconverging cutting edges for cooperation with the cutting edges of theledger blade, the angle of the cutting edges of'the ledger blade beingmore than the angle of the cutting edges of the knife, and a separatingand ledger blade backing plate positioned above the ledger blade andprovided with an opening for receiving the upper end of the knife.

38. A pinking mechanism for sewing machines having a base, comprising aledger blade spaced above the base and provided with an opening formingconverging cutting edges, a vertically reciprocatory knife supportedbelow the base and having converging cutting edges for cooperation withthe cutting edges of the ledger blade, means for maintaining the cuttingedges of the blade and knife in yieldable engagement with each otherduring cutting movements of the knife, and a separating and ledger bladebacking plate positioned above the ledger blade.

39. A pinking mechanism for sewing machines having a base, comprising astationary ledger blade spaced above the base and provided with anopening forming converging cutting edges, a vertically reciprocatoryknife supported below the base and having converging cutting edges forcooperation with the cutting edges of the ledger blade, the angle of thecutting edges of the ledger blade being more than the angle of thecutting edges of the knife, means cooperating with the knife formaintaining the cutting edges of the blade and knife in yieldableengagement with each other during cutting movements of the knife, and aseparating and ledger blade backing plate positioned above the ledgerblade.

40. A pinking mechanism for sewing machines having a base, comprisingastationary ledger blade spaced above the base and provided with anopening forming converging cutting edges, a. vertically reciprocatoryknife supported below the base and having converging cutting edges forcooperation with the cutting edgesof the ledger'blade, the angle of thecutting edges of the ledger blade being more than the angle of thecutting edges of the knife, means cooperating with the knife formaintaining the cutting edges of the blade and knife in yieldableengagement with each other during cutting movements of the knife, and aseparating and ledger blade backing plate positioned above theledgerblade and provided with an opening for receiving the upper end ofthe knife.

41. A trimming mechanism for sewing machines having a base, comprisingupper and lower cooperating cutting elements normally disposed inineffective cutting position below the base, and manually operable meansfor raising said cutting elements to effective cutting position whereinthe upper cutting element is disposed above the base, or for effectingthe depression of said cutting elements to their normal position belowthe base.

42. A trimming mechanism for sewing machines having a base, comprisingupper and lower cooperating cutting elements normally disposed inineffective cutting position below the base, and manually operable meansfor raising said cutting elements as a unit to effective cuttingposition wherein the upper cutting element is disposed above the base,or for effecting the depression of said cutting elements to their normalposition below the base.

43. A pinking mechanism for sewing machines comprising a base having anopening, a support mounted below the base, a ledger blade spaced abovethe opening and mounted on the support, said ledger blade beingprovidedwith an opening forming converging cutting edges, a knife levermounted on the support below the base to swing about a horizontal axis,a knife mounted on said lever and projecting upwardly through saidopening for cooperation with the cutting edges of said ledger blade,means for oscillating said knife lever, and a backing plate for theledger blade mounted on said support for retaining the said bladeagainst being moved by the thrust of 44. A pinking mechanism for asewing machine having a base and adapted to be mounted below the base ofthe sewing machine, which pinking mechanism comprises cooperating,relatively reciprocatory, pinking knives conjointly operative to effect.acut in a substantially horizontal plane when mounted on a sewingmachine,'and means disposed below the cutting plane of the knives foreflfecting relative reciprocatory movement of the pinking knives.

, 45. A pinking mechanism for a sewing machine having a base and.adapted to be mounted below the base of the sewing machine, whichpinking mechanism comprises-relatively reciprocatory, pinking knives'conjointly operative to efiect a cut in a substantially horizontalplane when mounted on a sewing machine, means disposed below the cuttingplane of the knives for effecting relative reciprocatory movementof thepinking knives, and means forpositioning the machine with one of saidpinking knives disposed above the base of the sewing machine.

46. A'p'inking mechanism for a sewing machine having a base and adaptedto be mounted below the base of the sewing machine, which pinkingmechanism comprises cooperating, relatively reciprocatory, pinkingknives having converging cutting edges conjointly operative when mountedon a sewing machine to efiect a V- shaped cut in a substantiallyhorizontal plane,

and means disposed below the cutting plane of the knives for efiectingrelative reciprocatory movement of the knives.

4'7. A pinking mechanism for a sewing machine having a base andadaptedto be mounted below the base of the sewing machine, which pinking ingmechanism comprises cooperating, relatively 7o mechanism comprises aledger blade having an mechanism comprises cooperating, relativelyreciprocatory, pinking knives having converging cutting edgesconjointlyoperable when mounted on a sewing machine to eifect a V-shapedcut in a substantially horizontal plane, a lever for effecting relative,reciprocatory movement of the knives pivotally mounted below the cuttingplane of the knives for oscillation about an axis substantially parallelto the cutting plane of'the knives, and means for maintaining the knivesin yieldable engagement during cutting movement of the knives.

48. A pinking mechanism for asewing machine having a base and adapted tobe mounted below the base of a sewing machine, which pinking mechanismcomprises cooperating, relatively reciprocatory, pinking knives havingconverging cutting edgesconjoin'tly operable when mounted.

on a sewing machine to effect 'a V-shaped cut in a substantiallyhorizontal plane, a lever for effecting relative, reciprocatory movementof the knives pivotally mounted below the cutting plane' of the knivesfor oscillation about an axis substantially parallel to the cuttingplane of the knives, and means cooperating with the lever andreciprocatory, pinking knives having convergin cutting edges conjointlyoperable when mounted on a sewing machine to efiect a V-shaped cut in asubstantially horizontal plane, a lever for effecting relative,reciprocatory movement of the knives pivotally mounted below the cuttingplane' of the knives for oscillation about an axis substantiallyparallel to the cutting plane of the knives, means cooperating with thelever and one of the knives for maintaining the knives in yieldableengagement during cutting movement of the knives and means forpositioning the pinking mechanism below the base of a sewing machinewith one of said knives disposed above the base of the sewing machine.

50. A pinking mechanism for a sewing machine having a base and adaptedto be mounted below the base of a sewing machine, which pinkingmechanism comprises cooperating, relatively reciprocatory, pinkingknives having converging 'cutting edges conjointly operable when mountedon a sewing machine to effect a V-shaped cut in a substantiallyhorizontal plane, a lever for effecting relative, reciprocatory movementof the having a base and adapted to be mounted below i the base of thesewing machine, which pinking mechanism comprises a ledger blade havingconverging cutting edges and arranged to lie parallel to the base of thesewing machine, a lever pivotally mounted below the plane of the ledgerblade for oscillation about an axis parallel to the plane of the ledgerblade, a knife pivotally mountedon the lever for cooperation with theledger blade, and means cooperating with the knife and lever formaintaining the knife inyieldable engagement with the ledger bladeduring cutting movement of the knife.

52. A pinking mechanism for a sewing machine having a base and adaptedto be mounted below the base of the sewing machine, which pinkingmechanism comprises a ledger blade having converging cutting edges andarranged to lie parallel to and spaced above the base of the sewingmachine, a lever pivotally mounted below the plane of the ledger bladefor oscillation about an axis parallel to the plane of the ledger blade,a knife having converging cutting edges pivotally mounted on the leverfor cooperation withthe ledger blade, and means cooperating with theknife and lever for maintaining the knife in yieldable engagement withthe ledger blade during cutting movement of the knife.

.53. A pinking mechanism for a sewing machine having a base and adaptedto be mounted below the base of the sewing machine, which pinkingmechanism comprises a ledger blade having an opening forming convergingcutting edges and arranged and positioned to lie in a'horizontal planeparallel to and spaced above the base of the sewing machine, avertically reciprocatory knife supported below the plane of the ledgerblade and having converging cutting edges for cooperation with thecutting edges of the ledger blade.

54. A pinking mechanism for a sewing machine having a base and adaptedto be mounted below the base of the sewing'machine, which pinkingopening forming converging cutting edges and arranged and positioned tolie in a horizontal plane parallel to and spaced above the base of thesewing machine, a vertically reciprocatory knife supported below theplane of the ledger blade and the sewing machine, a verticallyreciprocatory knife supported below the plane of the' ledger blade andhaving converging cutting edges for cooperation with the cutting edgesof the ledger blade, and means for maintaining the cutting edges of theblade and knife in yieldable engagement with each other during cuttingmovement 1 of the knife. I

56. A pinking mechanism for a sewing machine having a base and adaptedto be mounted below the base of the sewing machine, which pinkingmechanism comprises a stationary ledger blade having an opening formingconverging cutting edges and arranged and positioned to lie in ahorizontal plane parallel to and spaced above the base of the sewingmachine, a vertically reciprocatory knife supported below the plane ofthe ledger blade and having converging cutting edges for cooperationwith the cutting edges of the ledger blade, and means cooperating withthe knife for maintaining the cutting edges of the blade and knife inyieldable engagement with each other during cutting movements of theknife.

57. A pinkingmechanism for a sewing machine having a base and adapted tobe mounted below the base of the sewing machine, which pinking mechanismcomprises a stationary ledger blade having an opening forming convergingcutting edges and arranged and positioned to lie in' a horizontal planeparallel to and spaced above the base of the sewing machine, avertically reciprocatory knife supported below the plane of the ledgerblade and having converging cutting edges for cooperation with thecutting edges of the ledger blade, the angle of the cutting edges of theledger blade being greater than the angle of the cutting edges of theknife, and means for maintaining the cutting edges of the ledger bladeand knife in yieldable engagement with each other during cuttingmovement of the knife.

58. A pinking mechanism for a sewing machine having a base and adaptedto be mounted below the base of the sewing machine, which pinkingmechanism comprises a stationary ledger blade having an opening formingconverging cutting edges and arranged and positioned to lie in ahorizontal plane parallel to and spaced above the base of the sewingmachine, a vertically reciprocatory knife supported below the plane ofthe ledger blade and having converging cutting edges for cooperationwith the cutting edges of the ledger blade, the angle of the cuttingedges of the ledger blade being greater than the angle of the cuttingedges of the knife, and means cooperating with the knife for maintainingthe cutting edges of the ledger blade and knife in yieldable engagementwith each other during cutting movement of the knife.

GEOFFREY STEVENSON.

